/* * COPYRIGHT: See COPYING in the top level directory * PROJECT: Parallel Port Function Driver * FILE: drivers/parallel/parport/hardware.h * PURPOSE: Hardware definitions */ #ifndef _HARDWARE_H_ #define _HARDWARE_H_ /* * The following constants describe the various signals of the printer port * hardware. Note that the hardware inverts some signals and that some * signals are active low. An example is LP_STROBE, which must be programmed * with 1 for being active and 0 for being inactive, because the strobe signal * gets inverted, but it is also active low. */ /* * bit defines for 8255 status port * base + 1 * accessed with LP_S(minor), which gets the byte... */ #define LP_PBUSY 0x80 /* inverted input, active high */ #define LP_PACK 0x40 /* unchanged input, active low */ #define LP_POUTPA 0x20 /* unchanged input, active high */ #define LP_PSELECD 0x10 /* unchanged input, active high */ #define LP_PERRORP 0x08 /* unchanged input, active low */ /* * defines for 8255 control port * base + 2 * accessed with LP_C(minor) */ #define LP_PINTEN 0x10 #define LP_PSELECP 0x08 /* inverted output, active low */ #define LP_PINITP 0x04 /* unchanged output, active low */ #define LP_PAUTOLF 0x02 /* inverted output, active low */ #define LP_PSTROBE 0x01 /* inverted output, active low */ #endif /* _HARDWARE_H_ */